• 제목/요약/키워드: Level-crossing

검색결과 259건 처리시간 0.032초

LNG 저장탱크용 멤브레인 형상설계를 위한 유한요소해석 (Finite Element Analysis of the Corrugated Membrane of LNG Storage Tank for Its Geometric Design)

  • 김성원;이성우;이중남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.620-624
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    • 1997
  • Corrugated membranes which are used as a means of liquid- and gas-sealing for a LNG storage tank and provide one of the most reliable primary barrier are the main component of in-ground membrane types for the assurance of high safety. It absorbs large thermal and mechanical deformations caused by ultra low temperature of LNG, -162 .deg.c, the cryogenic liquid and mechanical deformations caused by was carried out on crossing corrugation by commercial F.E code, ANSYS. This paper presents some of results in stress analysis of membranes performed for the purpose to investigate the strength of existing membrane for LNG storage tank designed by IHI,MHI, KHI and KGC expect for Technigaz eariy published. Based on these analytical studies,design criteria were estabilished and SHI original membranes having a high level of safety and fitting to larger capacities were developed.

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철도교량 홍수시 열차운전규제기준에 대한 연구 (A study on the train passage control at railroad bridge under heavy rainfall)

  • 박영곤;이진욱;윤희택;목재균;김선종
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.1001-1006
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    • 2004
  • Railroad disasters are frequently occurred by man-made causes or natural causes. In general, man-made causes are illegal construction practices, deterioration with the lapse of time and railroad crossing accidents, and natural causes are rainfall. snow, wind, earthquake, etc. Of cause, railroad disasters by man-made causes are prevented from keeping the safety principle, constructing multi-level crossing, securing enough men of ability and financial resources and making a thorough check using equipments with high capacity. And railroad disasters by natural causes are also minimized by construction of disaster prevention facilities, introduction and operation of general disaster prevention system and reasonable train passage control. Therefore, to setup the criterion of train passage control for train safety at railroad bridge under heavy rainfall, risky factors, national and oversea criteria under such circumstances are reviewed and a scheme to setup the criterion is suggested.

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낙뢰 피해 최소화를 위한 공동 접지망 구성 (Common Earth Network constitution for minimize surge damage)

  • 김용규;백종현;최경일;류근수
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.190-195
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    • 2008
  • Surge proof equipment is an installation to make surge flow on the ground promptly so as to reduce surge-related damage on infrastructure, not to prevent surge from falling down on infrastructure directly. Compared with classical line individual earth, High speed line common earth has higher surge characteristic and plays a significant role to prevent infrastructure damage and injuries from surge, or short circuit accident between 25kV catenary and rail. In this paper, we analyzed the case of accident that caused communication/signaling system impaired while a tractor crossing level crossing at Honam line; in addition, we examined the accident reduction measures to minimize injury and property damage from cutting accidents with respect to common earth network.

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역도 인상동작 불안정성 수준에 따른 발바닥 체성감각요인 분석 (Factor Analysis of the Somatosensory for Foot according to the Instability Level of Snatch Lifting)

  • Moon, Young Jin
    • 한국운동역학회지
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    • 제30권1호
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    • pp.7-16
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    • 2020
  • Objective: It is to find factors related to stability through analysis of plantar pressure factors according to the level of instability when performing Snatch. Method: Foot pressure analysis was performed while 10 weightlifters performed 80% of the highest level of Snatch, and motion was classified and analyzed in 3 grades according to the level of instability. Results: First, in Bad Motion, the movement distance of the pressure center in the direction of ML and AP was larger significantly in Phase 2. Second, in Phase 2, the number of zero-crossing in the AP direction was larger statistically significantly in Good Motion. Third, in the bad motion in Phase 3, the number of zero-crossing in the ML direction showed a significantly larger value. Fourth, in Phase 4, it was found that the more stable the lock out motion, the greater the activity of foot controlling in the left and right directions. Fifth, Phase 3, the greater the Maximum/Mean foot pressure value, the more stable the pulling action. Sixth, in Phase 2, the foot pressure was concentrated with a wide distribution in the midfoot and rearfoot. Seventh, the triggering number of the forefoot region was small in the last pull phase. Eighth, the number of triggers in the toe area was significantly higher during Good Motion in Phase 4. Conclusion: Summarizing the factors of instability in Snatch, there was no significant difference in Phase 1 for each condition. In order to enhance the stability in Phase 2, the sensory control ability in the AP direction is required, and focusing the foot pressing motion with a wide distribution in the middle and rear parts increases the instability. In Phase 3, it was found that the more unstable, the more sensory control activity was performed in the ML direction, the stronger the forefoot pressing action should be performed for a stable Snatch. In Phase 4, It is important that the feet sensory control activity in ML directions and the control ability of the toes in order to have stable Lock out motion.

Impaired Avoidance Learning and Increased hsp70 mRNA Expression in Pentylenetetrazol-treated Zebrafish

  • Kim, Yeon-Hwa;Lee, Yun-Kyoung;Lee, Han-Sol;Jung, Min-Whan;Lee, Chang-Joong
    • Animal cells and systems
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    • 제13권3호
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    • pp.275-281
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    • 2009
  • The effects of pentylenetetrazol (PTZ), a GABA receptor antagonist, were studied on passive avoidance learning and expression of heat shock protein 70 (hsp70), neuroglobin, and fatty acid binding protein-7 (fabp-7) genes. Zebrafish were trained to stay in a dark compartment to avoid a weight dropping in an acryl shuttle box with a central sliding door. In two training sessions of 2 h interval, each consisting of 3 trials, the crossing time was significantly increased from $43.2{\pm}14.4s$ to $149.3{\pm}38.5s$ in the first training session and remained $116.1{\pm}36.0s$ s in the first trial of the second training session in the control. In zebrafish treated with PTZ before the first training session, the crossing time was significantly increased neither in the first nor in the second training session. However, the increased crossing time was maintained in the second training session when 10 mM PTZ was treated three times for 10 min at 30 min intervals between the first and second training session. Quantitative real-time PCR showed that expression level of hsp70 mRNA increased two to eight fold over that of control in the brain at 0-24 h after termination of PTZ treatment. No change in expression of neuroglobin and fabp-7 mRNA was shown in PTZ-treated zebrafish. Our studies suggest that PTZ impairs learning ability in avoidance response and also modifies expression of genes related to the neuroprotection.

An M/G/1 queue under the $P_{\lambda,\tau}^M$ service policy

  • Kim, Jong-Woo;Lee, Ji-Yeon
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2005년도 춘계학술대회
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    • pp.25-29
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    • 2005
  • We analyze an M/G/1 queueing system under $P_{\lambda,\tau}^M$ service policy. By using the level crossing theory and solving the corresponding integral equations, we obtain the stationary distribution of the workload in the system explicitly.

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A SIMPLE APPROACH TO THE WORKLOAD ANALYSIS OF M/G/1 VACATION QUEUES

  • Kim, Nam-Ki;Park, Yon-Il;Chae, Kyung-Chul
    • Journal of the Korean Statistical Society
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    • 제33권2호
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    • pp.159-167
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    • 2004
  • We present a simple approach to finding the stationary workload of M/G/1 queues having generalized vacations and exhaustive service discipline. The approach is based on the level crossing technique. According to the approach, all that we need is the workload at the beginning of a busy period. An example system to which we apply the approach is the M/G/1 queue with both multiple vacations and D-policy.

차상신호시스템에서의 건널목 신호보안설비 인터페이스 (Interface of Level crossing signal equipment in on-board signal mode)

  • 김용규;백종현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.1451-1453
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    • 2004
  • 본 논문은 기존선 전철화 및 속도 향상 관련 건널목 신호보안 설비에 대해 검토하였다. 이는 건널목 경보제어기, 정 시간 제어장치, 조차장 또는 역 주변에서의 건널목 운영 방안, 전철화에 따른 건널목 인명 및 신호보안 설비 보호방안 등을 중점적으로 분석하였으며, 또한 2004년부터 시작된 기존선 차상신호시스템 도입에 따라 기존의 건널목 신호보안 설비와 차상신호시스템과의 인터페이스 방안에 대해서도 함께 분석하였다.

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A probabilistic seismic demand model for required separation distance of adjacent structures

  • Rahimi, Sepideh;Soltani, Masoud
    • Earthquakes and Structures
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    • 제22권2호
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    • pp.147-155
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    • 2022
  • Regarding the importance of seismic pounding, the available standards and guidelines specify minimum separation distance between adjacent buildings. However, the rules in this field are generally based on some simple assumptions, and the level of confidence is uncertain. This is attributed to the fact that the relative response of adjacent structures is strongly dependent on the frequency content of the applied records and the Eigen frequencies of the adjacent structures as well. Therefore, this research aims at investigating the separation distance of the buildings through a probabilistic-based algorithm. In order to empower the algorithm, the record-to-record uncertainties, are considered by probabilistic approaches; besides, a wide extent of material nonlinear behaviors can be introduced into the structural model by the implementation of the hysteresis Bouc-Wen model. The algorithm is then simplified by the application of the linearization concept and using the response acceleration spectrum. By implementing the proposed algorithm, the separation distance in a specific probability level can be evaluated without the essential need of performing time-consuming dynamic analyses. Accuracy of the proposed method is evaluated using nonlinear dynamic analyses of adjacent structures.

Breeding of Productive Bivoltine Hybrid, CSR16${\times}$CSR17 of Silkworm Bombyx mori L.

  • Reddy, N.Mal;Basavaraja, H.K.;Kumar, N.Suresh;Joge, P.G.;Kalpana, G.V.;Dandin, S.B.;Datta, R.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제8권2호
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    • pp.129-133
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    • 2004
  • The breeding work was initiated by utilizing two Japanese hybrids namely C135${\times}$N134 and N137${\times}$C146 along with two evolved Indian breeds, J14 and A24. The breed CSR16 which is characterized with marked larvae and white dumbbell cocoons was evolved from the Japanese hybrid C135${\times}$N134 by crossing with J14, while the breed CSR17 which is characterized with plain larvae and white oval cocoons was evolved from the Japanese hybrid N137${\times}$C146 by crossing with A24. The hybrid of these evolved breeds i.e., CSR16${\times}$CSR17 has shown superior over control hybrid $KA{\times}{NB_4}{D_2}$ and on par with the ruling hybrid of CSR2${\times}$CSR4. The hybrid CSR16${\times}$CSR17 was authorized during 1999 by Central Silk Board, Bangalore, Government of India for commercial exploitation during favourable months based on national level race authorization test.